Red-Eyes Wyvern!!!

i would like to ask about the effect of "Red-Eyes Wyvern".....can i use his effect in opponent's end phase???it says at an end phase in which i did not normal summon or set....so in my opponent's turn, i did not normal summon or set....can someone help with this???

and about the eff it should be like this..During your End Phase, if you did not Normal Summon or Set a monster this turn, you can remove from play this card from your Graveyard to Special Summon 1 "Red-Eyes" monster from your Graveyard, except "Red-Eyes B. Chick